The research is designed to continue a clinical evaluation of the efficacy of Dialetical Behavior Therapy (DBT) with chronically suicidal women with Borderline Personality Disorder (BPD), and to examine the impact of therapist in-session behaviors on client compliance/cooperation, suicidal behaviors, and therapeutic alliance. In the treatment outcome study, 24 females with a history of multiple parasuicides and a diagnosis of Borderline Personality Disorder will be randomly assigned to DBT or a community treatment-as-usual control group. DBT subjects will be seen for one year by one of five therapist trained in DBT. The control group will be referred as usual to treatment in the community but will be assessed at the same intervals as the experimental subjects. To analyze the effects of DBT vs. the control condition, the subjects in this study will be combined with those in a prior pilot study conducted in an almost identical fashion. To examine the relationship of therapist in-session behavior on client behavior, the individual therapy tapes for the 24 subjects from this and the pilot study will will be subjected to sequential content analyses. We will examine therapist variables such as use of DBT strategies and other therapist behaviors characteristic of behavior therapy and client in-session behaviors such as resistance/cooperation and suicidal verbalizations as well as between session behaviors such as completion of homeword assignment and phone calls to the therapist.